Mass and Chemistry of Organic Horizons and Surface Mineral Soils on Watershed 1 at the Hubbard Brook Experimental Forest, 1996 - present
TITLE
Mass and Chemistry of Organic Horizons and Surface Mineral Soils on Watershed 1 at the Hubbard Brook Experimental Forest, 1996 - present
PRINCIPAL INVESTIGATOR(s)
Chris Johnson
Department of Civil and Environmental Engineering, Syracuse University
151 Link Hall
Syracuse, NY 13244
USA

Phone: (315) 443-4425
Thomas G. Siccama
Yale School of Forestry and Environmental Studies
OTHERS INVOLVED
Mary Margaret Koppers
Department of Civil and Environmental Engineering, Syracuse University
151 Link Hall
Syracuse, NY 13244
USA
Ellen Denny
National Phenology Network
ABSTRACT:
This data set includes chemistry of O-horizons ("forest floor") and the 0-10 cm mineral soil layer in Watershed 1 at Hubbard Book. Calcium in the form of wollastonite (CaSiO3) was added to Watershed 1 in October 1999. The application rate was 1028 kg Ca per ha, and the application was relatively uniform across the watershed. Pre-treatment forest floor surveys were completed in 1996 and 1998. The first post-treatment forest floor survey was completed in 2000. This data set includes mass and thickness data for the sampled layers. Chemical data include concentrations and pools of organic matter, C, N, Ca, Mg, K, P, Mn, Fe, Al, Cu, Pb, and Zn. Soil pH and exchangeable Al, Ca, Mg, K, and H are also included. Sampling is intended to continue at 4 or 5 year intervals.
KEYWORD SET: Hubbard Brook Ecosystem Study LTER
aluminum, base cations, calcium, carbon, copper, forests, forest floor, HBEF Watershed 1, HBR, Hubbard Brook LTER, iron, lead, magnesium, manganese, nitrogen, organic matter, phosphorus, potassium, pH, soil, soil horizons, trace metals, watersheds, zinc.
KEYWORD SET: LTER Core Research Areas
inorganic nutrients, organic matter.
BEGIN DATE
1996
END DATE
2010
LOCATION
Watershed 1 is an 11.8 ha watershed extending from the weir at 488 m to the ridge at 747 m.
West bounding coordinate: -71.730866
East bounding coordinate: -71.725832
North bounding coordinate: 43.959356
South bounding coordinate: 43.952121
Elevation
Minimum: 488
Maximum: 747
(Unit: meter)
SITE DESCRIPTION
Samples were collected in Watershed 1 of the Hubbard Brook Experimental Forest. Watershed 1 is forested by typical northern hardwood species (sugar maple, beech and yellow birch) on the lower 90% of its area and by a montane boreal transition forest of red spruce, balsam fir and white birch on the highest 10%. Hydrology and stream water chemistry have been monitored since 1963. Standard surveying techniques were used in 1996 to install a grid system of 200 grid cells, each 25 x 25 m square (slope corrected). These grid units serve as the coordinate system for sample plot selection. For more spatial information please visit the following links:
http://www.hubbardbrook.org/watersheds/maps/w1_grid_map.htm
http://www.hubbardbrook.org/watersheds/w1_grid_elevations.htm
SAMPLING DESIGN
Plots were chosen to be sampled prior to each sampling trip by using a random number generator to identify 100 plots over the entire watershed. The location of the sampling site within each plot was determined by selecting two random integers between 0 and 24 ("x" and "y") and navigating to the selected coordinates from the northwest corner of the 25 x 25 m plot. The number of plots sampled varies from 58 to 101 per sampling year.
FIELD COLLECTION PROCEDURES
Once a sampling point was located by taping (occasionally by pacing), a 15 x 15 cm template was placed on the forest floor and 4 nails were inserted through pre-drilled holes, one in each corner. The nails hold the template in place on the forest floor and retain the forest floor material within the sample area beneath the template. A keyhole saw, pruning shears and a trowel were used to make a clean cut around the template, thus isolating a block of the forest floor. The surrounding forest floor material was scraped back from the block leaving it as a pedestal. This block was then undercut at the organic-mineral soil boundary with a trowel, and pruning shears used to sever any roots. Using a trowel inserted beneath the block and hands on top, the block was carefully picked up and turned over such as to rest on the template. Any remaining mineral soil was carefully scraped away "up" to the bottom of the Oa layer of the forest floor. After all mineral soil was removed, the total thickness of the block and the thickness of the combined Oi and Oe horizons (referred to in this data set as "Oie") were measured at 5 cm intervals along each of the four sides for a total of 8 measurements. The average thickness of the Oa horizon could then be determined by subtraction of the average Oie thickness from the average total thickness for each block. The block was separated into Oie and Oa horizons in the field. Each horizon was placed in a separate plastic bag for return to the laboratory.
After removal of the organic horizons, the upper 10 cm of the mineral soil was sampled by coring. A stainless steel corer (diameter 1.362 inches 1996-2010, diameter 1.374 inches 2014 onward) was inserted in the soil below the forest floor. If the core length exceeded 10 cm, the core was cut to 10 cm and bagged. If the core length was less than 10 cm, usually due to refusal by stones, the entire core was bagged. Two full 10-cm cores, or up to four partial cores, were collected at each site, unless mineral soil was absent.
LABORATORY PROCEDURES
Upon return to the laboratory, all samples were air dried to a constant weight. For 1996-2006, the Oie horizon sample was oven dried at 80oC. From 2010 onward, the Oie was air dried. The Oie samples were ground in a Wiley mill to pass a 2-mm screen. Large solid sticks and roots larger than the size of a pencil and obviously alive or fresh material were removed and weighed. These large pieces were not ground and were not included in the mass calculations. The Oa horizon was sieved through a 5-mm stainless steel screen. Sticks, roots and debris (coarse fraction) not passing through the screen with mild pressure were weighed. Stones, which were rarely present in the Oa horizon, were also included in the coarse fraction. Material passing through the screen was weighed and rebagged. The mineral soils were passed through a 2-mm stainless steel screen. Material passing through the screen was weighed and rebagged. Material not passing through the screen, including sticks, roots, and stones, was weighed. A subsample of each processed soil was weighed, oven dried at 80oC, and weighed again. An air dry to oven dry conversion factor was determined in order to express the total soil mass for each horizon on an oven dry weight basis. Samples of the ground/screened Oie, Oa, and mineral soils were put in 4 oz. glass jars for long-term preservation in the Hubbard Brook archives.
Organic content and acid-extractable metals determination
For determination of organic content and acid-extractable metals concentration, 0.5 g of the oven-dry ground material was placed in a pre-weighed crucible and ashed overnight at 500oC. The ashed material was cooled and weighed. The loss-on-ignition was computed and used as a measure of organic matter content. The ash was eluted with 10 ml of 6N HNO3 and heated for a few minutes (to a simmer) on a hot plate. The hot extract solution was poured through a filter paper (Whatman # 41 ashless) in a funnel and into a 50 ml volumetric flask. The crucible and the material on the filter paper were rinsed several times with distilled deionized water. The volume in the flask was brought up to 50 ml with distilled deionized water. The 50 ml of extract solution was stored at room temperature until chemical analysis. The extract solution was analyzed for metals on a combination of ICP-OES (Ca, Mg, K, P, Mn, Al, Fe) and ICP-MS (Cu, Pb, Zn). Analysis of plant tissue standard reference materials (e.g. apple leaves, pine needles) has consistently yielded near-100% recoveries, indicating that this digestion procedure is effective for digesting organic matter. However, digestion of Oa horizon and mineral soil samples in incomplete, as evidenced by residual mineral matter on the filter paper. It is therefore safest to refer to the results as "acid-extractable" rather than "total" element content. However, Johnson et al. (2014) showed that this extraction procedure can account for the Ca added to this watershed as wollastonite in 1999.
Exchangeable acidity and exchangeable aluminum (KCl extraction)
A 2.5 g sample of soil was extracted with ~50 mL of 1 M KCl for 12 hours using a mechanical vacuum extractor. The filtrate was collected, and exchangeable acidity was determined by titrating a subsample to the phenolphthalein endpoint using NaOH. In 2006 and 2010 a subsample of the filtrate was also analyzed for aluminum on ICP-OES.
Exchangeable base cations and exchangeable aluminum (NH4Cl extractions)
A 2.5 g sample of soil was extracted with ~50 mL of 1 M NH4Cl for 12 hours using a mechanical vacuum extractor. The filtrate was analyzed for calcium, magnesium, sodium, and potassium on ICP-OES. In all years but 2010, aluminum was included in the ICP-OES analysis. From 2002 onward, silica was also included in the ICP-OES analysis.
Total carbon and nitrogen
A subsample of air-dried soil was ground in a mortar and pestle and dried at 80oC for at least 24 hours. The dried soil was analyzed for carbon and nitrogen by elemental analysis.
Soil pH
Two grams of organic soil, or 10 g of mineral soil, was mixed with 9.9 mL DIW. The solution was shaken thoroughly and pHw was measured. Next, 0.1 mL of 1 M CaCl2 was added to create a 0.01 M CaCl2 solution. The sample was shaken periodically through 30 minutes and pHs was measured.
CALCULATIONS
Concentrations of carbon, nitrogen and exchangeable cations in all samples were calculated on an oven-dry-weight basis. Exchangeable cation concentrations are corrected for blank samples. One procedural blank sample was included for each ten soil samples. For organic horizons, total mass is the sieved mass of soil for the horizon multiplied by the ratio of oven dry soil to air dry soil masses and divided by the area of the template used for sampling (15 x 15 cm). For the mineral horizon, total mass is the average sieved mass of soil in the cores multiplied by the ratio of oven dry soil to air dry soil masses and divided by the diameter of the soil corer. Organic mass is the total mass of soil in the horizon multiplied by the loss on ignition for the horizon. Concentrations of elements in the forest floor were calculated on an oven dry weight basis. Total amounts of the elements were estimated on a per square meter basis by extrapolating up from the 15 x 15 cm sample mass. Forest floor thickness, species contributing litter to the sample site, and E horizon intensity for each plot are given in dataTable 1. Total mass, organic matter mass, LOI, acid extractable metals, and CN are presented in Table data2.
NOTES
Pools are the product of the chemical concentration and the total mass for each horizon. Exchangeable hydrogen can be estimated by subtracting exchangeable Al from exchangeable acidity. Effective cation exchange capacity can be estimated by summing the exchangeable base cations (Ca, Mg, K) and exchangeable acidity. Effective base saturation can be calculated as the percent of effective CEC accounted for by base cations.
Between 2006 and 2010, sampling responsibilities were transferred from field crew at Yale University School of Forestry to Syracuse University Civil and Environmental Engineering. Notes on tree species in Table ww1_ffe.txt are much less detailed beginning in 2010.
REFERENCES
  • Cho, Y., Driscoll, C.T., Johnson, C.E., and Siccama, T.G. 2010. Chemical changes in soil and soil solution after calcium silicate addition to a northern hardwood forest. Biogeochemistry 100(1-3):3-20.
  • Cho, Y., Driscoll, C.T., Johnson, C.E., Blum, J.D., and Fahey, T.J. 2012. Watershed-level responses to calcium silicate treatment in a northern hardwood forest. Ecosystems 15(3):416-434.
  • Johnson, C.E., Driscoll, C.T., Blum, J.D., Fahey, T.J., and Battles, J.J. 2014. Soil chemical dynamics after calcium silicate addition to a northern hardwood forest. Soil Science Society of America Journal 78:1458-1468.
DATA ACCESS GUIDELINES
Data Use Policy



The re-use of scientific data has the potential to greatly increase communication, collaboration and synthesis within and among disciplines, and thus is fostered, supported and encouraged. Permission to use this dataset is granted to the Data User free of charge subject to the following terms:

1) Acceptable use. Use of the dataset will be restricted to academic, research, government or other not-for-profit professional purposes.

2) Redistribution. The data and metadata are provided for use by the Data User. The Data User will not redistribute the original Data Set or metadata to others without the explicit permission of the Principal Investigator.

3) Citation. It is considered a matter of professional ethics to acknowledge the work of other scientists. Thus, the Data User will properly attribute the Data Set in any publications or in the metadata of any derived data products that were produced using the Data Set. Citation should take the following general form: Creator, Year of Data Publication, Title of Dataset, Publisher, Dataset identifier.

Citation example: Holmes, R.T. 2012. Bird Abundances at Hubbard Brook (1969-2010) and on three replicate plots (1986-2000) in the White Mountain National Forest. Durham, NH. Hubbard Brook Data Archive [Database]. http://hubbardbrook.org/data/dataset.php?id=81 (23 July 2012)

4) Acknowledgment: The Data User should acknowledge any institutional support or specific funding awards referenced in the metadata accompanying this dataset in any publications where the Data Set contributed to its content. Acknowledgments should identify the supporting party, the party that received the support, and any identifying information such as grant numbers.

Acknowledgment example: Data on [topic] were provided by [name of PI] on [date]. These data were gathered as part of the Hubbard Brook Ecosystem Study (HBES). The HBES is a collaborative effort at the Hubbard Brook Experimental Forest, which is operated and maintained by the USDA Forest Service, Northern Research Station, Newtown Square, PA. Significant funding for collection of these data was provided by [agency]-[grant number], [agency]-[grant number], etc.

5) Consultation and questions. Data users are strongly encouraged to consult with the Principal Investigator(s) who collected these data for further information. Also, when appropriate, Data Users should consider including the Principal Investigator as a collaborator and/or co-author in the use of these data.

6) Notification. The Data User will notify the Principal Investigator of any publication or derivative work based on the Data Set. The Data User will also provide the Principal Investigator and/or the administrator of the Hubbard Brook Ecosystem Study with a pdf or two reprints of any publication(s) resulting from use of the Data Set.

7) Disclaimer. While substantial efforts are made to ensure the accuracy of data and documentation contained in this Data Set, complete accuracy of data and metadata cannot be guaranteed. All data and metadata are made available "as is". The Data User holds all parties involved in the production or distribution of the Data Set harmless for damages resulting from its use or interpretation.

8) Terms of Agreement. By accepting this Data Set, the Data User agrees to abide by the terms of this agreement. The Data Owner shall have the right to terminate this agreement immediately by written notice upon the Data User's breach of, or non-compliance with, any of its terms. The Data User may be held responsible for any misuse that is caused or encouraged by the Data User's failure to abide by the terms of this agreement.



CONTACT PERSON

Information Manager, Hubbard Brook LTER
234 Mirror Lake Road
North Woodstock, NH 03262
USA

Phone: (603) 726-8902
Email: hbr-im@lternet.edu

Data file: w1_ffa.txt
Description: Hubbard Brook forest floor and surface mineral soil data, Watershed 1. Element amounts, element concentrations, C, N and organic matter content measured in 15x15 cm excavated organic horizon soil blocks; exact number of samples varies by sampling year.
Notes on Data: Original field data sheets are at Syracuse University, Civil and Environmental Engineering. Data was last updated in 2015. Samples of forest floor material in jars will be located in the USFS archive building at the HBEF in Woodstock, NH.
ColumnVariableDescriptionUnitsCoded?Missing value label
1Site_IDUnique sample idnoneynone
2YearSample yearYYYYnnone
3PlotPlot Numbernoneynone
4HorizonSoil Horizonnoneynone
5pHwSoil pH determined in waterpHn
-888.88
-999.99
6pHsSoil pH determined in 0.01 M CaCl2pHn
-888.88
-999.99
7PercentNPercent nitrogen contentdimensionlessn
-888.88
-999.99
8PercentCPercent carbon contentdimensionlessn
-888.88
-999.99
9ExAcidcmolc_kgExchangeable acidity determined by titration of 1 M KCl extract centimoleChargePerKilogramn
-888.88
-999.99
10ExCacmolc_kgExchangeable calcium determined in 1 M NH4Cl extract, cmolc kg-1centimoleChargePerKilogramn
-888.88
-999.99
11ExMgcmolc_kgExchangeable magnesium determined in 1 M NH4Cl extract, cmolc kg-1centimoleChargePerKilogramn
-888.88
-999.99
12ExNacmolc_kgExchangeable sodium determined in 1 M NH4Cl extract, cmolc kg-1centimoleChargePerKilogramn
-888.88
-999.99
13ExKcmolc_kgExchangeable potassium determined in 1 M NH4Cl extract, cmolc kg-1centimoleChargePerKilogramn
-888.88
-999.99
14ExAlcmolc_kgExchangeable aluminum determined in 1 M NH4Cl extract, cmolc kg-1centimoleChargePerKilogramn
-888.88
-999.99
15ExSicmolc_kgExchangeable silica determined in 1 M NH4Cl extract, cmol kg-1centimolePerKilogramn
-888.88
-999.99
16ExAl_KClcmolc_kgExchangeable aluminum determined in 1 M KCl extract, cmolc kg-1centimoleChargePerKilogramn
-888.88
-999.99
17Ca_g_m2Calcium amount by horizongramPerMeterSquaredn
-999.99
18Mg_g_m2Magnesium amount by horizongramPerMeterSquaredn
-999.99
19K_g_m2Potassium amount by horizongramPerMeterSquaredn
-999.99
20P_g_m2Phosphorous amount by horizongramPerMeterSquaredn
-999.99
21Mn_g_m2Manganese amount by horizongramPerMeterSquaredn
-999.99
22Cu_g_m2Copper amount by horizongramPerMeterSquaredn
-999.99
23Zn_g_m2Zinc amount by horizongramPerMeterSquaredn
-999.99
24Pb_g_m2Lead amount by horizongramPerMeterSquaredn
-999.99
25Al_g_m2Aluminum amount by horizongramPerMeterSquaredn
-999.99
26Fe_g_m2Iron amount by horizongramPerMeterSquaredn
-999.99
27Ca_mg_kgCalcium concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
28Mg_mg_kgMagnesium concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
29K_mg_kgPotassium concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
30P_mg_kgPhosphorous concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
31Mn_mg_kgManganese concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
32Cu_mg_kgCopper concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
33Zn_mg_kgZinc concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
34Pb_mg_kgLead concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
35Al_mg_kgAluminum concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
36Fe_mg_kgIron concentration by horizon as ppm of oven dry samplemilligramPerKilogramn
-888.88
-999.99
37TMOven dry wt of total mass of horizon (kg/m2)kilogramPerMeterSquaredn
-999.99
38OM_OMOven dry wt of organic matter mass of horizon (kg/m2)kilogramPerMeterSquaredn
-999.99
39LOILoss on ignition (percent)dimensionlessn
-999.99

CODES

Variable: Site_ID
Description:
unique string containing Year-watershed-plot-horizon
Variable: Plot
Description:
A counting number representing one of the 200 plots on Watershed 1
Variable: Horizon
Code
Description
Oie
Oie horizon
Oa
Oa horizon
min
Mineral soil, top 10 cm beneath the organic horizon

MISSING VALUE CODES
Variable
Missing Value Code
Code Explanation
pHw
-888.88
-999.99
Sample not collected
Sample not analyzed
pHs
-888.88
-999.99
Sample not collected
Sample not analyzed
PercentN
-888.88
-999.99
Sample not collected
Sample not analyzed
PercentC
-888.88
-999.99
Sample not collected
Sample not analyzed
ExAcidcmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
ExCacmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
ExMgcmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
ExNacmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
ExKcmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
ExAlcmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
ExSicmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
ExAl_KClcmolc_kg
-888.88
-999.99
Sample not collected
Sample not analyzed
Ca_g_m2
-999.99
Data not available
Mg_g_m2
-999.99
Data not available
K_g_m2
-999.99
Data not available
P_g_m2
-999.99
Data not available
Mn_g_m2
-999.99
Data not available
Cu_g_m2
-999.99
Data not available
Zn_g_m2
-999.99
Data not available
Pb_g_m2
-999.99
Data not available
Al_g_m2
-999.99
Data not available
Fe_g_m2
-999.99
Data not available
Ca_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
Mg_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
K_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
P_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
Mn_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
Cu_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
Zn_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
Pb_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
Al_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
Fe_mg_kg
-888.88
-999.99
No sample collected.
Data not available.
TM
-999.99
Data not available
OM_OM
-999.99
Data not available
LOI
-999.99
Data not available

Data file: w1_ffe.txt
Description: Hubbard Brook Forest Floor Data, Watershed 1. Field data and measurements for 15x15 cm excavated organic and mineral horizon soil blocks; exact number of samples varies by sampling year.
Notes on Data: Original field data sheets are at Syracuse University, Civil and Environmental Engineering. Data was last updated in 2015. Samples of forest floor material in jars will be located in the USFS archive building at the HBEF in Woodstock, NH.
ColumnVariableDescriptionUnitsCoded?Missing value label
1YearSample yearYYYYnnone
2PlotPlot Numbernoneynone
3E_CodeE horizon development intensitynoney
-9999
4Sp_1One of the three most important canopy tree species over the plotnoney
NA
5Sp_2One of the three most important canopy tree species over the plotnoney
NA
6Sp_3One of the three most important canopy tree species over the plotnoney
NA
7FF_Thickness1One of eight measures of thickness of forest floor block (in centimeters)centimetern
-999.9
8FF_Thickness2One of eight measures of thickness of forest floor block (in centimeters)centimetern
-999.9
9FF_Thickness3One of eight measures of thickness of forest floor block (in centimeters)centimetern
-999.9
10FF_Thickness4One of eight measures of thickness of forest floor block (in centimeters)centimetern
-999.9
11FF_Thickness5One of eight measures of thickness of forest floor block (in centimeters)centimeternnone
12FF_Thickness6One of eight measures of thickness of forest floor block (in centimeters)centimetern
-999.9
13FF_Thickness7One of eight measures of thickness of forest floor block (in centimeters)centimetern
-999.9
14FF_Thickness8One of eight measures of thickness of forest floor block (in centimeters)centimetern
-999.9
15Oie_Thickness1One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
16Oie_Thickness2One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
17Oie_Thickness3One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
18Oie_Thickness4One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
19Oie_Thickness5One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
20Oie_Thickness6One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
21Oie_Thickness7One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
22Oie_Thickness8One of eight measures of thickness of Oie (in centimeters)centimetern
-999.9
23Core_1Length of one of four possible mineral soil cores collected.centimetern
-999.9
24Core_2Length of one of four possible mineral soil cores collected.centimetern
-999.9
25Core_3Length of one of four possible mineral soil cores collected.centimetern
-999.9
26Core_4Length of one of four possible mineral soil cores collected.centimetern
-999.9

CODES

Variable: Plot
Description:
A counting number representing an existent plot
Variable: E_Code
Code
Description
0
absent
1
weak "salt and pepper"
1.5
moderate
2
good, clearly present
3
excellent, deep and well-developed
Variable: Sp_1
Code
Description
ABBA
Abies balsamea (Balsam fir)
ACSA
Acer saccharum (Sugar Maple)
ACSP
Acer spicatum (Mountain maple)
ACPE
Acer pensylvanicum (Striped maple or moose wood)
ACRU
Acer rubrum (Red maple)
BEAL
Betula alleghaniensis (Yellow birch)
BEPA
Betula papyrifera (White or paper birch)
FAGR
Fagus grandifolia (American beech)
FRAM
Fraxinus americana (White ash)
PIRU
Picea rubens (Red spruce)
SOAM
Sorbus americana (Mountain ash)
Variable: Sp_2
Code
Description
ABBA
Abies balsamea (Balsam fir)
ACSA
Acer saccharum (Sugar Maple)
ACSP
Acer spicatum (Mountain maple)
ACPE
Acer pensylvanicum (Striped maple or moose wood)
ACRU
Acer rubrum (Red maple)
BEAL
Betula alleghaniensis (Yellow birch)
BEPA
Betula papyrifera (White or paper birch)
FAGR
Fagus grandifolia (American beech)
FRAM
Fraxinus americana (White ash)
PIRU
Picea rubens (Red spruce)
SOAM
Sorbus americana (Mountain ash)
Variable: Sp_3
Code
Description
ABBA
Abies balsamea (Balsam fir)
ACSA
Acer saccharum (Sugar Maple)
ACSP
Acer spicatum (Mountain maple)
ACPE
Acer pensylvanicum (Striped maple or moose wood)
ACRU
Acer rubrum (Red maple)
BEAL
Betula alleghaniensis (Yellow birch)
BEPA
Betula papyrifera (White or paper birch)
FAGR
Fagus grandifolia (American beech)
FRAM
Fraxinus americana (White ash)
PIRU
Picea rubens (Red spruce)
SOAM
Sorbus americana (Mountain ash)

MISSING VALUE CODES
Variable
Missing Value Code
Code Explanation
E_Code
-9999
Data not available
Sp_1
NA
Data not available
Sp_2
NA
Data not available
Sp_3
NA
Data not available
FF_Thickness1
-999.9
Data not available
FF_Thickness2
-999.9
Data not available
FF_Thickness3
-999.9
Data not available
FF_Thickness4
-999.9
Data not available
FF_Thickness6
-999.9
Data not available
FF_Thickness7
-999.9
Data not available
FF_Thickness8
-999.9
Data not available
Oie_Thickness1
-999.9
Data not available
Oie_Thickness2
-999.9
Data not available
Oie_Thickness3
-999.9
Data not available
Oie_Thickness4
-999.9
Data not available
Oie_Thickness5
-999.9
Data not available
Oie_Thickness6
-999.9
Data not available
Oie_Thickness7
-999.9
Data not available
Oie_Thickness8
-999.9
Data not available
Core_1
-999.9
Soil core not collected.
Core_2
-999.9
Soil core not collected.
Core_3
-999.9
Soil core not collected.
Core_4
-999.9
Soil core not collected.